<?php
declare(strict_types=1);
namespace PhpMyAdmin\SqlParser\Components;
use PhpMyAdmin\SqlParser\Component;
use PhpMyAdmin\SqlParser\Parser;
use PhpMyAdmin\SqlParser\Token;
use PhpMyAdmin\SqlParser\TokensList;
use function implode;
use function is_array;
/**
* `ORDER BY` keyword parser.
*
* @final
*/
class OrderKeyword extends Component
{
/**
* The expression that is used for ordering.
*
* @var Expression
*/
public $expr;
/**
* The order type.
*
* @var string
*/
public $type;
/**
* @param Expression $expr the expression that we are sorting by
* @param string $type the sorting type
*/
public function __construct($expr = null, $type = 'ASC')
{
$this->expr = $expr;
$this->type = $type;
}
/**
* @param Parser $parser the parser that serves as context
* @param TokensList $list the list of tokens that are being parsed
* @param array<string, mixed> $options parameters for parsing
*
* @return OrderKeyword[]
*/
public static function parse(Parser $parser, TokensList $list, array $options = [])
{
$ret = [];
$expr = new static();
/**
* The state of the parser.
*
* Below are the states of the parser.
*
* 0 --------------------[ expression ]-------------------> 1
*
* 1 ------------------------[ , ]------------------------> 0
* 1 -------------------[ ASC / DESC ]--------------------> 1
*
* @var int
*/
$state = 0;
for (; $list->idx < $list->count; ++$list->idx) {
/**
* Token parsed at this moment.
*/
$token = $list->tokens[$list->idx];
// End of statement.
if ($token->type === Token::TYPE_DELIMITER) {
break;
}
// Skipping whitespaces and comments.
if (($token->type === Token::TYPE_WHITESPACE) || ($token->type === Token::TYPE_COMMENT)) {
continue;
}
if ($state === 0) {
$expr->expr = Expression::parse($parser, $list);
$state = 1;
} elseif ($state === 1) {
if (
($token->type === Token::TYPE_KEYWORD)
&& (($token->keyword === 'ASC') || ($token->keyword === 'DESC'))
) {
$expr->type = $token->keyword;
} elseif (($token->type === Token::TYPE_OPERATOR) && ($token->value === ',')) {
if (! empty($expr->expr)) {
$ret[] = $expr;
}
$expr = new static();
$state = 0;
} else {
break;
}
}
}
// Last iteration was not processed.
if (! empty($expr->expr)) {
$ret[] = $expr;
}
--$list->idx;
return $ret;
}
/**
* @param OrderKeyword|OrderKeyword[] $component the component to be built
* @param array<string, mixed> $options parameters for building
*
* @return string
*/
public static function build($component, array $options = [])
{
if (is_array($component)) {
return implode(', ', $component);
}
return $component->expr . ' ' . $component->type;
}
}